Means for rolling sheet metal



2 Sheet-heet I Sept. 25, 1945. c. JONES MEANS FOR ROLLING SHEET METAL Filed. May 23 1942 j n w I a r I I r r I I I I I I l I I l I l n l I III II w/ TNESJ @W 7 Sept, 25, 1945.

c. G. JONES MEANS FOR ROLLING SHEET METAL Filed ma 25, 1942 2 Sheets-Sheet 2 Patented Sept. 25, 1945 UNITED STATES PATENT OFFICE r 2,385,627 MEANS FOR ROLLING snna'r rm'rAL our G. Jones, Youngstown, on. Application May 23, 1942, Serial No. 444,218

6 Claims.

tics distinctly superior to those of articles of the same classes producedin accordance with present practices.

My invention is concerned with the production of improved surface finishes, and to a lesser degree with reformation and/or modification of internal stress, grain structure or the like; it is moreover especially applicable to the production I of sheets from alloys which are capable of precipitation hardening and of metal coated sheets.

It is perhaps of paramount utility and advantage in connection with the manufacture" of sheets and strips of relatively thin or light gage, but it may alsobe employed to advantage in the production of heavy sheets and plates, espe cially when a highly finished outer surface, either on the plate itself or on a galvanized, tinned. or other metal coating thereon, is required.

Thus in its broader aspects the invention contemplates subjecting metal to rolling pressure while at substantially constant elevated temperature and in continuous contact with a fluid medium having a high degree of heat conductivity as compared to air, whereby the effects of rapid temperature changes during or at about the time of rolling, virtually unavoidable under present,

practices, may be eliminated entirely and the metal thus freed of their effects. I

Another object of the invention is to roll metal, either bare or coated with a layer of another metal, in such way as to minimize friction between the rolls and the metal surface" whereby the roughness and irregularity heretofore pro-, duced or preserved in such surfaces during rolling can be prevented, or removed after production as a result of preliminary treatment.

. common in manufacturing such foils in accordance with present practices. Thus hard and soft spots in isolated areas, resulting in pinching off or in the production of thickness irregularities suchas wavesor the like, and scratching, dullnessor other impairment of the metal surface are entirely eliminated, while the life of the rolls themselves is prolonged by minimizing their deteriorationduring rolling.

Furthermore since the invention permits rolling to finished gage without reheating or allowing the metal to come into contact with the air or other oxidizing medium while it is in highly heated condition, it is evident that oxide scale cannot form during the rolling and impair the thereby with the aid of apparatus embodying certain of its features illustrated in the accom- A further object is the provision of a method of and means for rolling metal while submerged in a fluid medium maintained at a strain-relieving temperature whereby not only is the surface finish improved but the production of excessive internal stresses and/or undesirable grain modification during rolling is avoided, while. in some instances the internal structural characteristic, as well as the surface finish, may be materially enhanced.

Another objectof the invention is to permit a reduction. especially of the more readily oxidizalble metals such as magnesium, aluminum or the like, from relatively heavy slabs or billets to thin sheets or strips of final or finished gage without intermediate heating steps betweensuccessivepasses through the reducing rolls, and while maintaining the metal at substantially conpanying drawings, in which: I

Fig. 1 is a diagrammatic longitudinal section showing mechanism adapted for rolling single sheets in accordance with the invention on a Z-high" rolling mill comprising .a single pair of rolls;

Fig. 2 is a corresponding illustration of a 2-high mill arranged for rolling coiled strip;

Fig.3 similarly illustrates the practice of the invention where the strip is not coiled, butis instead folded upon itself in a space below the rolls; Fig. 4 shows certain of the apparatus included in a continuous electrolytic tin plate roduction line combined with mills adapted in accordance with the invention to enhance the quality and character of the electrolytic coatings produced; Fig. 5 is a generally similar'diagram of another electrolytic tin'plate line in which but one side of a strip at a'time is subjected to electrolytic plating and the strip rolled after each plating operation;

Fig. 6 is a more detailed side elevation on an enlarged scale of a roll stand such as may be used in the apparatus shown in any of the preceding figures, the stand here shown, being ,of the 4-hig h type embodying two working rolls and two backing up rolls: and v Figs. 7-10 inclusive are further enlarged fragclusive in Fig. 6, not necessarily all on the same 3 scale, but showing in greater detail the construction of the several parts of themechanism.

In the several figures like characters areused 'to designate the same parts.

Referring now more particularly to the drawings and especially to Figs. 1-5 inclusive, it 'will be understood that while I have diagrammatically indicated 2-high roll stands in each case 4-high stands, cluster mills or any other desired type might be employed as the invention is not limited to the use of any specific kind or character of rolling mill or number or dimensions of the rolls included therein provided they be adequate for the performance of their intended functions while the fluid containers, conveyor rolls, reels, idlers, supports therefor andother mechanical elements indicated, as well as details relating to their erection and operation are likewise sub'ject to modification within preference or choice as influenced by circumstances.

Thus in Fig. 1 I have illustrated mechanism Y comprising a fluid tight reservoir RI in which is disposed a feed and runout table T adapted to support a sheet SI within the. reservoir and beneath thesurface of a fluidcontalned in the latter. The fluid level is preferably maintained. sub

stantially constant at about the line Fl appreciably above the plane of table T, which is interrupted at its midpoint where the reservoir is deepened to provide space for a mill MI 'which in this 1 instance, as noted, comprisesbut a single pair of rolls r, r' provided with suitable driving mechanism (not shown) and adiustably mounted for The rotation on vertically spaced parallel axes. lower roll r is submerged in the fluid in the reservoir and the upper one r at least extends below the surface Fl sufficiently to enable sheet SI to be kept entirely submerged as it is rolled back "heated fluid usually facilitates themaintenance mentary sections on the lines 1'! to Il)| inlubricating properties at the desired temperature but it will be obvious this is not essential for many of those herein specifically mentioned are suitable for use at temperatures approaching, if not-.

exceeding, 600 F. notwithstanding that at such temperatures their-efficacy as lubricants is virtually non-existent. It is thus largely a matter of choice, within the limitations mentioned, what fluid is employed, and as the choice is necessarily 1 influenced by the temperature to be maintained,

mining in advance the optimum values under all possible conditions.

As a guide, however, but not as a limitation, it

may be stated that while it is not necessary to I regard technical distinctions between "hot rollof uniform temperature therein and permits the jfluid to be filtered or clarified as well, if desired. I

The fluid in the reservoir may be any relatively inert or non-corrosive one such as water, if thereduction of the metal is to be carriedout at a temperature of less-than 212 F. or, if at a higher temperature, a suitable oil or other substance which is fluid, but not dangerously-inflammable I or volatile, at that temperature.

'I'hus' linseed, palm, castor and cotton seed oils, vegetable or animal cooking fats, such as cocoanut oil, lard or shortening compounds, or glycerine and other relatively high boiling point hydrocarbons, including' synthetic and/or minjeraLoils, may also be used, and in general any suitable fluid devoid, or substantially devoid,-of

free or available oxygen or other medium which might attack the-metal it contacts" may be considered as within the contemplation of the invention whichqrequires primarily that air be excluded from the pass or nip of the rolls, and from contact with the metal being rolled before, after and during rolling, and that the air-excluding medium be one not more harmful to' the metal than air at the temperature employed.

ing" and cold rollingv in considering the ternperature to be employed in any specific instance,

it is usually desirable to roll iron and other relatively high melting point metals at temperatures below the lower limits of the temperatures usually designated as "hot rolling" temperatures for .their hot rolling" range and above their respective minimum recrystallizaaition temperatures.

Returning now to the drawings, it will be understood that Figs. 2-5 inclusive-merely diagrammatically illustrate several situations in which the principles of-the invention may be utilized in mechanisms specifically adapted for rolling metal in different ways and under different circumstances.

Thus, in Fig. 2 I have shown a mill M2 for rolling coiled strip, this mill comprising a pair of rolls t V r, r' on opposite sides of which are disposed reels N,=N submerged in. a reservoir R2 adapted to maintain a heated fluid at a level F2 above the nip of the rolls. This mill is of the same-general character as that known in the trade as ,a Steckel mill and is thus preferably provided with means (not shown) for driving either reel while maintaining the strip S2 ,under back tension by braking the other reel as the strip is unwound from it during passage back and forth between the rolls from one reel to the other. Such mill is of especial advantage for producing strip with exceptionally high surface finish, which can be obtained by a liberal use of tension through proper control of the reels during the rolling, and

as the presence of the liquid makes the initial angle between the roll and surface of the metal sharper than it would be if no liquid were pres- It will be understood that the temperature of' the liquid in the reservoirR2 is maintained by suitable apparatus (not shown) which may inelude either a heating unit disposed within, or

partly within, the reservoir or a separate heated reservoir communicating with reservoir R2 through suitable conduits, a pump, filter or other desired equipment also being supplied As this equipment may be of any desired character there is no necessity for illustrating or, describing it in further detail.

The apparatus shown in Fig. 3 is likewise best suited to rolling strip material and is of particular advantage when the extremely high surface finish obtainable with the aid of that illustrated in Fig. 2 is not required, since it can be erected and operated at appreciably less expense to produce moderately highly finished strips in accordance with the invention. It comprises a reservoir R3 provided with sufficient fluid to keep the pass between rolls 1', r' of mill M3 beneath the fiuid level F3, strip S3 running between rolls I on either side of the roll pass and folding or. looping upon itself in the lower part of the reservoir as it is rolled back and forth. The action of the strip is thus substantially in accordance with customary practice in strip mills provided with looping pits sincereservoir R3 is tosome extent comparable to such a pit, and its details willbe understood from the drawings.

In Fig. 4 I have illustrated an electrolytic tin plate production line which includes a plating tank Pl in which are arranged several pairs of idler rollers I for looping the strip S4 as it receives a light electrolytic coating of tin, after which it passes over other idlers through a water wash contained in a tank WI and next into a reservoir R4 in which is .positioned a mill M4 for rolling the strip beneath the surface F4 of the fluid in the reservoir. This initial rolling of the strip after a light coating of tin has been deposited upon it in plating tank Pl permits the finish of the coating to be improved without danger of inducing its transformation to gray or alpha tin under the influence of the. rolling pressure. The temperature of the fluid in reservoir R4 is therefore preferably maintained at about 190 F. which is similar to that of'the plating bath and as the first coating is rolledwhile still very thin,

minimize or exclude "pin holes or porosity in. I

the final tin coating onthe strip, for after the initial coating has been rolled and an improved finish thus imparted to it any pin holes or pores in it are at least partly sealed 'up and when the strip is then led through a second plating tank .PZ where a heavier second layer of tin is deposited over the first one, preferably to the extent of about twice the thickness of the'latter, the second coating fully covers any remaining'vpids- The strip is then washed in a tank W2. and finally passed through a second reservoir R5 where it is rolled in a partly submerged mill M5 before being withdrawn, cooled and dried preparatory to the usual operations which normally follow electro lytic plating of strip. In view of the preliminary rolling of the strip after receiving its first tin' coating in plating tank ,Pl, any thickness variation in the coating acquired in the second tank P2 is of less extent than would be the case if the first coating had not been made uniform in thickness before the second was applied, and it is therefore apparent that even before being rolled inmill M5 the coated strip carries-a more uniform layer of tin than strips coated in usual electrolytic plating lines. Consequently when the strip is again rolled in mill M5 the uniformity of thickness in its coating is still further enhanced while any remaining minor defects resulting from the plat- 5 ing are simultaneously minimized or entirely removed.

As a modification of the plating line shown in Fig. 4.it may 'be preferable to utilize one long plating tank, passing the strip in loops over a large number of idlers and interposing a suitable number of mills at intervals between adjacent loops, since the rolling of the plating contemplated by my invention can be carried out as well in the plating solution as in another fiuid'kept in a separate reservoir; that is, the plating solution in installations with which I am familiar is normally kept at a temperature in the neighborhood of 190 F., and such temperature is entirely suitable for the rolling operation on tin plate in accordance with my invention. It would, of course, be superfluous to illustrate this modification or to give a more detailed description of it, but it may be suggested that a continuous plating line of this character having 48 complete loops up and down in the plating tank with means disposed at one or more intervals between adjacent loops for rolling the strip may be operated satisfactorily at approximately 190 F. in the production of tin I plate of high quality and exceptional surfac finish.

Another way of producing such tin plate in accordance with the invention is illustrated in Fig. 5 in which a plating tankP3 is provided with idlers and other equipment suitable for plating only one side of a strip S5 at'a time; near it is a wash water tank W3 where the strip is freed of residual plating solution and a reservoir R6 where the washed strip is rolled beneath the surface of a suitable fluid maintained at a level F6 above the pass of the'rolls of mill M6 partly submerged in the reservoir. The strip after the initial rolling, which imparts a high finish to the coating on one side, then moves into a second-plating tank F P4 suitably disposed to permit the opposite side of the strip to be plated therein before being washed in water tank W4 and then again rolled in reservoir R! by partly submerged mill M'|. As electrolytic tin plate lines of this general character are incommon use it is believed no further description thereof is herein required, the rolling carried out on mills M6 and M1 being generally comparable in its effect upon the tin plate surface to that performed on the strip when plated in accordance with the procedure described in connection-with the plating line shown in Fig. 4, the base metal in either case suffering no permanent reduction in thickness although the" coating may be slightly reduced as it is smoothed. From the foregoing it will be evident my invention permits rolling at moderatelyelevated temperatures under non-oxidizing conditions and with ample fluid present at the areas of contact between the rolls and the work, whereby a film of the fluid may be entrained 'in the rolling pass, tends to insulate the work from the rolls and produce the high surface finish, especially on metal coated articles, and reduced surface porosity which-result from practice of the invention. Ob-

viously, by keeping the rolling temperature well below the meltingpoint of the coating metal I am-able to stop the coating apparatus at any point without impairment from excessive temperature of any of the partly finished material undergo ins treatment. I

Rolling coated metals in accordance with the invention additionally imparts to thecoating a high degree of adherence and appreciably greater density than obtainable by present methods, and probably as a result of the combined effects of the rolling pressure and moderately elevated temperature, diffusion of the coating metal into the tion its surface, increase its density and compact it to the base before it has had opportunity to become oxidized. This prevents adherence of the coating to the rolls, which might occur if it were permitted to come into contact with air before rolling and thus avoids the production of spangled or mottled tin coatings when tin is used as the coating metal, while the rolling in of oxide, which impairs the quality of the'coating, is also prevented.

, Likewise it is impossible for particles of dust or other contamination to be rolled dry into the work surface and the absence of excessive internal strains prior to and during rolling enables a fully aged product to be obtained directly from the rolling mill without subsequent processing. a/

wall a metal plate I cut away to permit fluidtight roll neckglands to be mounted thereon for reception of the necks of certain of the rolls; Adjacent the edge of the resulting aperture is secured a reinforcing strip 2 which stilIens the plate edge and affords suflicient thickness of material to permit gland supporting plates to be firmly attached to the reservoir wall. Strip 2 may be welded to plate I and thusin effect hecomes a part of the latter, while a fixed gland plate 3 is secured thereto by cap screws 4 with a gasket 5 interposed between the strip and the plate to insure fluid tightness of the joint. Plate 3 carries a gland 6, hereinafter more fully described, through which'the neck 1 of the lower backing up roll 8 extends, while the upper edge of the plate is rabbeted out as best indicated in Fig. 9, to form a fluid tight joint with a super-v jacent gland plate l0 rabbeted in a complementary way so the two plates are in the same plane, while asbestos filled tubular copper gaskets ll set in suitable grooves in the plates and compressed by bolts IZ'afid nuts l3 fastening the plates together effectively seal the joint. Cap screws I 4, similar to screws 4, hold plate In against gasket 5 and in fixed position on the reservoir wall, and gland-6' receiving the neck l5 of lower working roll l6 permits it to turn without allowing the fluid in the reservoir to escape.

Inasmuch asthe upper working roll I1 must be adjustable with respect to the lower one I 6, a

These and other advantages previously mentioned are readily-obtainable with the aid of equipment such as that to which I have more or less generally referred, and it is believed it will be readily apparent therefrom to those skilled in the art how the method contemplated by the invention is practised, as the details of construction of the various parts of the equipment are capable of variation and modification within wide limits and the practice of the said method is not to be considered as restricted to the use of apparatus such as that thus far shown and described.

However, in order to facilitate a complete disclosure of the latter and also to demonstrate one modification therein which has occurred to me, I

have illustrated in Figs. 6-10 inclusive and shall now more fully explain certain mechanism I have devised which promotes the attainment of excelsimilar mounting for its neck gland 6" cannot be used, although the gland itself may be similar in its construction to glands 6' and 6 on the lower rolls.

The upper working roll gland 6" therefore is carried on a sliding plate l8 adapted to overlie the adjacent lateral edges of reinforcing strip 2 and adjustably secured thereto by the side arms of a U-shaped clamping plate 2!! bearing on gasket 5 and held to the strip by cap screws 24.

The lower edge of sliding plate l8 lies closely adjacent gland plate III which carries the lower lent results in the practice of the invention and.

which may therefore be utilized in con nection with any of the mills suitable for the purpose whether or not included among those illustrated in the preceding figures;

Thus, while I have referred for convenience more directly to roll stands of the "2-high type y it is of course contemplated that 4-high stands 'may be substituted therefor, and Figs. 6-10 inclusive illustrate in detail how a 4-high stand may conveniently be constructed for use in any of the situations mentioned.

, It will be recognized that although in accord-, ance with the invention it is essential that the working portions of the surfaces of the rolls be submerged in'a heated fluid while in rolling eontact with the work, it is usually preferable to have their bearings remote from the fluid where they can be kept at a lower temperature, preferably not in excess of about 160 F., and also that the rolls must have a capacity for adjustment to vary 7 the width of the roll pass. 1

Consequently to-attai-n these ends .in a 4-high roll stand I may employ for each reservoir side working roll gland-6' and in the-same plane, so

" the horizontal part of clamping'plate 20, secured to plate In by cap'screws 2,5, overlies both plates and facilitates the maintenance of a fluid tightv joint, asbestos filled tubular copper gaskets 26 being interposed between plates I 0 and 20. The side arms of the latter moreover are grooved to receive hollow tubular copper gaskets 21 and the lateral edges of the sliding plate are grooved in a complementary manner so together these two 7 plates'entirely enclose the vertical parts of gaskets 21, while adjacent the horizontal lower edge of the sliding plate a single relatively wide 'groove 28 is provided for the reception of gaskets 21 to afford a limited capacity for vertical adjustment of the upper working roll I! with sliding plate I8, gaskets 21 preferably being kept'under internal hydraulic pressure by suitable connections (not shown) with their ends. to be made it is usually only requisite to relieve the pressure in gaskets 21 but of course if desired the clamping plate screws 24, 25 also may be loosened; under some conditions, however, even the relief of the pressure in. the gaskets may not be necessary. In a 4-high, mill the upper backing-up roll 29 need not dip into the liquid in the reservoir and no gland to prevent loss of liquid adjacent its neck is required so it can and generally will be usual. y 4 I In referring to glands 6, G'and 6" I have pointed out they'may be of similar construction When an adjustment is mounted in ordinary bearings as adjustably secure the latter to the wall, the apand it is believed this will be evident upon more detailed explanation of'Fig. 8 in which glands 6' and 6" appear. in section on a common radial plane so a description of but one of them will sufiice, being applicable as well to the others. Thus gland 6' comprises a collar 30 welded to gland plate l and having internal threads at its outer end. Within the collar, gland plate In is rabbeted to receive a gasket 3| against which a packing ring 32 bears and the opposite face. of this ring is grooved'to receive a cooling tube 33, also fitting in a complementary groove in an outer packing ring 35. The function of this tube, which has connections 36, 31 with a circulating supply of cooling fluid, is to keep the temperature of the parts adjacentthe roll neck suflicientlylow to retain appreciable viscosity in the adjacent fluid in the reservoir whereby leakage of the latter through the glands is minimized. Compressible packing material 38 also surrounds the roll a neck and is compacted against packing ring 35 bya follower 39 threaded into fixed collar 30 and having circumferentialflat faces 40 for the reception of a spanner or other suitable tool whereby it can be set up. Thus it ,will be evident that while the roll necks can readily turn in the glands, the escape of the heated fluid from within the reservoir is prevented while overheating of the roll bearings through excessive conduction along their necks of heat received from the said fluid is minimized by the cooling efiect obtained ,from circulation of fluid through tubes in the glands.

It will be understood that the practice of the method of my invention is not restricted or limited to use of the novel mechanism just described although the latter is presently preferred since it is well adapted for the purpose. Furthermore, while certain changes and modifications in the said method have herein been suggested and reference made to specifically different arrangements of equipment adapted for its performance,

it will be understood that other changes and modifications in the apparatus as well as in the method itself will readily occur to those skilled in the .art and may be made-if desired without ertured plate and the clamping plate having complementary registering vertical semi-cylindrical groove adjacent the side edges of the apertured plate and non-complementary horizontal I grooves adjacent thebottom edge thereof, a continuous expandible tubular gasket disposed in said grooves, and means for supplying fluid under pressure to the interior of the gasket to thereby seal the joint between the plates against the passage of fluid therethrough'from the reservoir.

3. In mechanism of the class described, a reservoir having a wall, a roll within the reservoir having a neck extending through the wall, a roll neck gland fixed to the outer face of the wall comprising an internally threaded collar surrounding the roll neck,-grooved packing rings disposed in the collar, a tubular fluid conduit interposed between the rings substantially conforming to the groove therein and having fluid connectors externally of the collar, compressible packing engaging the packing ring remote i'rom'the reservoir, and a follower threaded into the collar operable to compress the packing against said packing ring and the latter against the conduit to thereby inhibit passage of fluid from the reservoir along the-roll neck.

' 4. In mechanism of the class described, a reservoir having a wall, an apertured plate slidable with respect thereto, a roll in the reservoir having a neck projecting therefrom through the aperture, a gland fixed to the plate and surrounding the neck adaptedto seal the plate and neck against the escape of fluid from the reservoir,

a clamping plate fixed to the reservoir to over lie the side and bottom edges of the apertured 1 plate and adapted to adjustably secure the latdeparting fromthe spirit and scope of the invention as defined in the appended claims.

Having thus described my invention, 1 claim and desire to protect by Letters Patent of the United States:

1. In mechanism 01' the class described, a reservoir having a wall, an apertured plate slidable with respect thereto, a roll in the reservoir hav ing a neck projecting therefrom through the aperture, a gland fixed tothe plate and surrounding the roll neck adapted to seal the plate and neck against the escape of fluid from the reservoir, and a generally U-shaped clamping plate fixed to the reservoir and overlying the side and bottom edges of the apertured plate adapted to adjustablysecure the latter to the wall.

2. In mechanism of the class described, a reservoir having a wall, an apertured plate slidable with respect thereto, a roll in the reservoir having the roll neck adapted to seal the plateand neck against the escape of fluid from the reservoir, a generally U-shape'd clamping plate fixed to the reservoir and overlying the side and bottom edges of the apertured plate adapted'to second plate slidable with respect to the wall ing a. neck projecting therefrom through the aperture, a'gland fixed to the plate and surroundthe plate.

ter to the wall, the clamping plate providing with the apertured plate a groove extending transversely below the roll neck, and an expandible gasket of less vertical width than'the groove disposed therein whereby to aiiord capacity for limited relative vertical adjustment of the plates without disturbing the normal position of the,

the reservoir, a pair of rolls within the reservoir having their necks respectively extending .through the glands, each gland including a CORP,

pressible fluid barrier surrounding the roll neck, means for compressing the barrier, and cooling liquid conducting means disposed between the barrier and the adjacent gland supporting plate.

6. In mechanism of the class described, a reservoir having a wall, a plate fixed thereto, a

and the first plate, a roll neck gland carriedby each plate exteriorly of the reservoir, a pair of rolls within the reservoir having their neckagrespectively extending through the glands, the latter each including a compressible fluid barrier I surroundingthe neck, means forcompressing the barrier, and cooling liquid conducting means surrounding each neck between the barrier and cam. o. JONES. 

